Lock and process of making the same



NOV. 10, 1936. J LACH 2,060,626 I LOCK AND PROCESS OF MAKING THE SAMEFiled April 22, 1953 INVENTOR E Law/d, Wm

ATTORNEY Patented Nov. 10, 1936 UNlTED STATE PATEli FFHQE LOCK ANDPROCESS OF MAKING THE SAM Application April 22, 1933, Serial No. 667,371

9 Claims.

This invention relates to cylinder lock plugs and to a particular methodof manufacturing the same.

More particularly, my invention is concerned with an improved processfor manufacturing a usual type of cast lock plug equipped with tumblerchambers, and is especially concerned with the formation of alongitudinal keyway in the plug arranged to traverse the tumblerchambers for guiding a key into contact with the tumblers.

More in detail, my invention relates to an improved type of die castplug having a series of independently walled transverse tumbler chambersand a keyway formed therein by the piercing of the walls separating thetumbler chambers after the plug is cast, whereby the keyway will betterguide a key inserted therein and will lend greater security to the lock.

For a description of my invention, I shall now refer to the drawingwherein Fig. 1 is an elevation of a usual type of sliding tumbler plugembodying my invention. Fig. 2 is a section along the lines 2-2 of Fig.l and Fig. 3 is a section along the lines 3-3 of Fig. 1. Fig. 4 is afront view of the plug illustrated in Fig. 1. Fig. 5 is a longitudinalsection of a plug after the chamber walls have been pierced. Fig. 6 is asectional View along the lines '66 of the plug of Fig. 5. Fig. '7 is adiagrammatical view illustrating the manner of cutting the keyway in thewalls separating the tumbler chambers. Fig. 9 shows a tool used in theprocess of Fig. 7, while Fig. 8 is a sectional View along the lines 88of Fig. '7.

Referring now more particularly to the drawing, reference numeral I0illustrates a usual type of die cast plug having a camming pin I l, ahead l2, and a series of tumbler chambers l3. Those skilled in the artwill readily appreciate that in accordance with the teachings of theprior art, there are only two ways of forming a keyway in a die castplug of the type shown in Fig. 1. One of the methods involves thecasting of the plug with a core the shape of the keyway inserted intothe front end of the plug in the direction of the arrow M. The use ofthis type of core will necessarily require the use of upper and lowercores for the forming of the tumbler chambers I3. These upper and lowercores must envelop the keyway core and mesh very closely and accuratelytherewith. It is quite obvious that this method of coring involvesconsiderable difficulty and is not at all desirable.

Another method which is now generally used commercially, involves theuse of upper and lower cores, which between them, form the tumblertumbler spring is adapted to ride.

chambers and also the usual key guiding lugs which protrude from thekeyway. However, these upper and lower cores must necessarily formdiametric openings on opposite sides of the diameter of the plug topermit their withdrawal, and therefore, leave no bottom portion, such asportion l5 of the keyway ll: as is illustrated in Fig. 6. Actually, thekeyway as formed by this last method will have nothing more than lugs,such as the lugs ll for supporting or guiding the key. There will be nokeyway such as is conventionally used in pin tumbler locks, in which thekeyway is sinuous in character and therefore controls the contour of thekey inserted therein, and also hinders picking.

By the method of manufacture which I prefer to utilize, the tumblerchambers 53 are formed by individual cores which leave transverse wallsl8 between the various chambers. Fig. 2 shows a cross section throughone of the tumbler chambers I 3 illustrating the formation thereof, andthe adjacent chamber I9 in which the usual type of Fig. 3 illustrates asection along the lines 3-3 of Fig. l and shows a wall 18 presentbetween each of the tumbler chambers.

Each of these walls is formed relatively thin so that it may be piercedby a tool 20 shown in Fig. 7, the cross section of which is the same asthe key to be used eventually, and is illustrated in Fig. 8. Thispiercing tool is guided in its piercing operation by a series of tools2| illustrated in Fig. 9, each of which has a cutout portion 22 of thesame contour as the tool 2i] and the key which is to fit the lock. Theseindividual guiding tools 2! are placed in each of the tumbler chambers13 as is illustrated in Fig. '7, and when the tool 20 descendsdownwardly in the direction of the arrow 23 it will pierce the walls l8and form therein a keyway IE to have guiding lugs I! and the supportingbottom l5. It will be interesting to note that when I utilize the seriesof guiding tools 2!, there is no way for the cut-out portions of theseparate walls to escape. Actually, only the first cut-out part is cutby direct contact with the tool 2i]. The second piercing is made by thefirst cutout portion as the tool forces that cut-out portion against thesecond wall. The second piercing in turn cuts the next tumbler wall etc.

It seems quite clear that by my invention, I am thus able to have aseries of independent tumbler chambers, and a key Way formed in the plugin such manner as to properly support and guide the key into the tumblerchambers. Also, by my invention, I have been able to dispense with theuse of complicated dies, such as were required in the prior art. While Ihave shown one method of forming my plug, it should be understood thatvariations of the same will readily occur to those skilled in the art,and that I consider my invention to be of broad and sweeping scope, anddo not wish to be limited in any monopoly which I may obtain except asmay be required by the state of the prior art.

I claim:

1. A tumbler plug having a series of tumbler chambers separated bywalls, and a pierced opening in each of said walls adapted to supportand guide the key for said plug, said pierced openings forming ineffect, the keyway for said plug.

2. The method of forming a tumbler plug which consists in first formingsaid plug with a plurality of tumbler chambers separated by walls, andthen piercing said walls to form the keyway of said plug.

3. A tumbler plug having a series of transverse tumbler chambersseparated from each other by walls, tumblers in each of said chambers,and a series of pierced openings through each of said walls forming inefiect a longitudinal keyway for said plug, each of said piercedopenings being of such contour as to guide the key and control thecontour of the key to be entered into the keyway.

4. The method of forming a plug which consists in first casting saidplug with a series of tumbler chambers completely separated by walls,and then piercing said walls to form a longitudinal keyway in effect,each of said piercings to be of such nature as to guide the key and tocontrol the contour of the key to be inserted into the keyway.

5. The method of forming a key plug which consists in first casting saidplug with a series of tumbler chambers completely separated by walls,inserting a series of guide members in said chambers, each of said guidemembers being pierced in a predetermined design conforming to the keywayto be formed in said plug, and then piercing the first wall with a toolformed like the piercings of said guide members and thereby forming insaid first wall a keyway opening, the metal cut-out of said wall beingoperable thereafter when forced downwardly by said tool to pierce thenext wall and so on.

6. The method of forming a plug which consists in first casting saidplug with a series of tumbler chambers completely separated byrelatively thin walls, and then piercing each of said walls to form alongitudinal keyway in effect, each of said piercings to be of suchnature as to guide and support the key in predetermined relation to saidtumbler chambers.

"I. The method of forming a plug of the sliding tumbler type in whichthe key traverses openings in the individual tumblers and is unsupportedand unguided in the plane of said tumblers, which consists in firstcasting said plug with a series of tumbler chambers completely separatedby relatively thin walls, and then piercing each of said Walls to form alongitudinal keyway in effect, each of said piercings to be of suchnature as to guide and support the key in predetermined relation to saidtumbler chambers.

8. The method of forming a tumbler plug in which the key is completelyunsupported and unguided in the planes of the tumblers, which consistsin first casting said plug with a series of tumbler chambers completelyseparated by relatively thin walls, and then piercing each of said wallsto form a longitudinal keyway in effect, each of said piercings to be ofsuch nature as to guide and support the key in predetermined relation tosaid tumbler chambers.

9. A tumbler plug having a series of transverse tumbler chambers.separated from each other by walls, tumblers in each of said chambers,and an opening substantially rectangular in form in each of said wallsand completely enclosed by portions of said walls, said openings beingaligned to form a, keyway and of such contour as to guide the keythrough said plug and to control the contour of the key.

JOSEPH F. LACH.

